import java.util.ArrayDeque;
import java.util.Deque;
import java.util.Stack;

public class LeetCode232 {

    /**
     * Your MyQueue object will be instantiated and called as such:
     * MyQueue obj = new MyQueue();
     * obj.push(x);
     * int param_2 = obj.pop();
     * int param_3 = obj.peek();
     * boolean param_4 = obj.empty();
     */
    class MyQueue {

        Stack<Integer> s1, s2;

        /** Initialize your data structure here. */
        public MyQueue() {
            s1 = new Stack<>();
            s2 = new Stack<>();
        }

        /** Push element x to the back of queue. */
        public void push(int x) {
            while (!s1.isEmpty()) {
                s2.push(s1.pop());
            }
            s1.push(x);
            while (!s2.isEmpty()) {
                s1.push(s2.pop());
            }
        }

        /** Removes the element from in front of queue and returns that element. */
        public int pop() {
            return s1.pop();
        }

        /** Get the front element. */
        public int peek() {
            return s1.peek();
        }

        /** Returns whether the queue is empty. */
        public boolean empty() {
            return s1.isEmpty();
        }
    }

}
